Based on the new 1-Series compact, the 116d EfficientDynamics uses a 116 horsepower, twin-turbocharged diesel engine and common rail injection to deliver almost 62 mpg on the European combined cycle. It can accelerate to 62 mph in 10.5 seconds.

With CO2 output proportional to fuel efficiency, that figure is also high enough to ensure the 116d sneaks below 100 grams per kilometer of the greenhouse gas. That ensures it dodges many of the CO2-based taxes and road charges imposed in European countries and cities. It's the first BMW (MINIs aside) to be granted this privilege.

BMW has previously sold another EfficientDynamics car in Europe, based on the previous generation 3-Series.

This used a stop-start system, aerodynamic 16-inch alloy wheels, Michelin energy-saver tires and longer gear ratios to achieve 57 mpg on the European cycle. The 116d EfficientDynamics will likely use similar techniques to hit its own target.

We should point out that, as ever, the European cycle is around 20-30 percent higher than you'd expect with EPA ratings. A realistic EPA figure for the 116d would be between 44 and 50 mpg combined, with an even higher highway figure.

Although the EfficientDynamics' power output seems low, it's torque that dominates the diesel driving experience, and it should make the 116d quite fun to drive.

Of course, since the 116d EfficientDynamics isn't coming to the U.S, it has to be declared a forbidden fruit. BMW may even pull its more powerful diesels in favor of hybrids soon, so for now at least, the prospect of a 60 mpg BMW is a little while off...

Still, if you want a green 1-Series, you can always lease a BMW Active-E. It's quieter, quicker, and looks better too!